function intersect(x1, y1, r1, x2, y2, r2 : double) : boolean;

var
	d : double;

begin
	d := sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
	result := (r1 + r2 >= d) and (r1 + d >= r2) and (r2 + d >= r1); 
end;
